Steam-engine recorder



8.11.0808311. Steam-Engine Recorder.

No. 228,179. Paremuwl 111.191,1880.

Mmm; i lInvalid/or' J 2:* Georgelfcro y ILPEERS. PHOTO-LITHOGRAPHER. WASHINGTON. D. C4

UNITED STATES PATENT OEEicE,A

r GEORGE H. CROSBY, OF SOMERVILLE, MASSACHUSETTS.

`STEAM-ENGINE RECORDER.

SPECIFICATION forming part of Letters Patent No. 228,179, dated June 1, 1880.

Application led December 13, 1879.

To' all whom it may concern:

Be it known that I, GEORGE H. CRosBY, of Somerville, of the county of Middlesex and State of Massachusetts, have invented a new and useful Improvement in Indicators for Steam-Engines; and I do hereby declare the same to be described in the following specification and represented in the accompanying drawing, which is a vertical section of an indicator provided with my said improvement, such indicator being ofthe kind as represented and described in Letters Patent of the United States No. 219,149, dated September 21,1879, and granted to me.

My invention relates to the rod of' the pist0n of the steam-cylinder of such indicator 5 and it consists in such rod as made tubular and to open at its lower end into or near such end to communicate with the steam-space of the cylinder, and provided at its upper end or between its ends with a partition or stop to prevent the steam from passing entirely through the rod or escaping from it at its upper end.

The said stop I usually form by boring the rod from each toward the opposite end of it until the two bores nearly meet, such bores varying in length, so as to bring the stop at or near the head of the cylinder when the piston is at or near its lowest position in the said cylinder. l

In this kind of indicator, as the pressure of steam in the cylinder varies materially during the upward stroke of the indicator-piston, it becomes very necessary, for the obtaining of good registry, that the piston should move rectilinearly, and with as little friction as possible. Therefore, it is a matter of import-ance that the piston-rod should be kept well lubricated, or that the lubricating material should not become stiff or hard, so as to impede the movement ofthe pistou-rod in the head of the cylinder.

It also is very necessary to have as light a rod as possible consistent with the strength or stiffness necessary to preventit from springing or binding' laterally during its sudden upward movement.

It has been found that by making the rod tubular, as described, instead of solid throughout its length, it may be larger in diameter,

comparatively speaking, and yet be as strong, if not stronger; and by having its bore open into the steam-space of the cylinder, so as to enable the steam to pass up within the rod and heat it, the lubricating material is rendered softer and caused to operate to better advantage, as in case of it becoming stiff or hardening upon the rodit will be melted or softened bythe heat. A

In order to prevent the rod when very thin from collapsing when the steam in the cylinder may be condensed, the stop, to prevent the emission of steam from the upper end of the rod, should be placed as low down in the rod as may be possible consistent with securing the necessary heating of the rod.

In the drawing, A denotes the cylinder, O the pistou, and B its rod, such rod being bored .in opposite directions from its two ends, as shown at a b, the bores not meeting, but being insulated from one another by the stop c.

The actuating-spring ofthe piston is shown at D and the piston-rod head at E, such head j being screwed upon the rod, the screw e for receiving the said head having upon it a checknut, f, as shown.

Another advantage of having the rod bored in opposite directions, as described, is that such enables the rod and piston-head when screwed together to be centered in a lathe and turned concentrically therein, the centers of the lathe being inserted in the bored ends of the rod. t

One or more minute holes lead from the foot of the Lipper bore of the piston-rod outwardly through the rod, as represented at t., they being for the purpose of enabling' the said upper bore to contain a lubricating material--such as tallow, for instance-which, on being heated by the steam let into the lower bore willv become softened or limpid and flow out upon the outer surface of the piston-rod, thence down the same to and upon the piston-head, whereby both rod and head may be lubricated as oceasion may require.

I claim as my invention as follows, viz:

1. The indicator piston-rod as tubular and opening at its lower end into or there communicating with the steam-space of the cylinder, and provided at its upper end or between its ends with the stop, as described, to prevent IOO the steam from escaping at the upper end of the rod, all being substantially as and for the purpose or purposes set forth.

2. The piston-rod as bored or tubular, pro- 5 vided with the stop,substantally as described.

3. The piston-rod as provided With a lubricant-reservoir and educt or educts thereof, a-rranged within it, substantially as set forth.

4. The piston-rod as provided With a lubril1o cant-reservoir and one or more ed/ucts thereto,

as set forth, and alsovwith a stemma-receivingv bore or space arranged in it (the said rod) und below the said reservoir, and to communicate with the steam-space of the cylinder, as de scribed.

GEORGE H. CROSBY.

Witnesses R. H. EDDY, W. W. LUNT. 

